The present invention relates to opening seals for automobiles and method of preparing the same having wire core embedded in installation base members thereof for increasing rigidity, which are installed along peripheries of door opening parts of automobile bodies for sealing openings between bodies and doors by making elastic contact with the doors when the doors are closed.
As shown in FIG. 8 and FIG. 9, an opening seal 10 for automobiles having a wire core 20 embedded therein has been well-known, which is mounted on a flange 3 installed along a periphery of a door 2 opening part on an automobile body 1 side for making elastic contact with the door 2 when the door 2 is closed to seal an opening between the body 1 and the door 2 (see, for example, the Japanese unexamined Patent Publication Nos. H03-82519 and 2004-322768).
FIG. 8 is a side view of an automobile having the opening seal 10 for automobiles mounted thereon; and FIG. 9 is an enlarged perspective view of an important, part of 100 of FIG. 8, showing the opening seal 10 for automobiles.
The opening seal 10 for automobiles comprises: a cross section roughly U-shaped installation base member 11 including an outer-cabin side wall 11a, an inner-cabin side wall 11b and a connecting wall 11c which connects the side the installation base member 11; and a protuberance 13 provided inside the inner-cabin side wall 11b of the installation base member 11, which makes elastic contact with and holds the flange 3. The outer-cabin side wall 11a has a plurality of projections 14 provided inside, which make elastic contact with the flange 3; and the installation base member 11 has a lip 15 provided on an inner-cabin side thereof. Decorative coating material 16 is provided from the lip 15 to a surface of the connecting wall 11c of the installation base member 11 for decorating appearance from an inner-cabin side.
As shown in FIG. 10 and FIG. 11, the wire core 20 embedded in the installation base member 11 of the opening seal 10 for automobiles comprises: a skeletal wire body 21 formed by consecutively bending a wire; and yarns 22, 23 partially connected with the wire body 21 for preventing expansion of the wire body 21 in a longitudinal direction. The wire core 20 is finally embedded in a longitudinal direction of the installation base member 11 while the wire core 20, consecutively bent into U shapes in the same direction at regular intervals in advance, is bent into a rough U-shape.
Examples of use of the yarns for preventing expansion of the wire body 21 in a longitudinal direction include: a plurality of non-thermo-fusible yarns 22 which do not melt at set vulcanization temperature for vulcanizing rubber component when preparing the opening seal 10 for automobiles as shown in FIG. 9 and FIG. 10 (six non-thermo-fusible yarns in FIG. 9 and FIG. 10); and a combination of the non-thermo-fusible yarns 22 which do not melt at the set vulcanization temperature and thermo-fusible yarns 23 which do not melt at the time of an extrusion molding and melt at the set vulcanization temperature as shown in FIG. 11 (two non-thermo-fusible yarns 22 and six thermo-fusible yarns 23 in FIG. 11).
Such a structure controls unnecessary expansion of the opening seal 10 for automobiles at the time of the extrusion molding and the preparation of the opening seal 10 for automobiles and improves rigidity of the installation base member 11 after molding, thereby improving assembly force of the opening seal 10 for automobiles on the flange 3.
In the opening seal 10 for automobiles prepared by extrusion molding, parts with the non-thermo-fusible yarn 22 are greatly improved in strength compared with parts without the non-thermo-fusible yarn 22. But, in the resultant opening seal 10 for automobiles having the full length including a corner part has caused problems that, on an outer peripheral side of a position 201 as an intersection of the hollow seal member 12 and a straight line 200, the hollow seal member 12 is subjected to force expanding toward an outer peripheral side whereas, on an inner peripheral side of the position 201, the hollow seal member 12 is subjected to contracting force which cause wrinkles. The straight line 200 connects the non-thermo-fusible yarn 22 (22a) embedded on a greater opening edge side on the outer-cabin side wall 11a of the installation base member 11 with the non-thermo-fusible yarn 22 (22b) embedded on a greater opening edge side on the inner-cabin side wall 11b of the installation base member 11.
The expansion and contraction of the hollow seal member 12 hamper stabilization of the assembled state of the opening seal 10 for automobiles, which degrades external appearance and sealing function. Such problems are remarkable when the folding wrinkles 202 generate.
As shown in FIG. 11, the Japanese unexamined Patent Publication No. H03-82519 discloses to connect each of three sides of the wire core 20, respectively embedded in the outer-cabin side wall 11a, an inner-cabin side wall 11b and a connecting wall 11c of the installation base member 11, with the yarns which are thermally degraded at the set vulcanization temperature and the yarns which are not thermally degraded (non-thermo-fusible yarn) at the set vulcanization temperature. The resultant opening seal is excellent in strength toward pulling force at the time of extrusion molding. But a way of disposing the yarns on each of the three sides of the wire core 20 is rough, only one side of the wire core 20 with the non-thermo-fusible yarn for example. Such a structure does not decrease expanding or contracting state on the hollow seal member 12 sufficiently, especially while the opening seal 10 for automobiles is assembled on the corner part.
The Japanese unexamined Patent Publication No. 2004-322768 discloses to provide high melting point yarn (non-thermo-fusible yarn) on a part of the inner-cabin side wall 11b, that is at least close to the connecting wall 11c. But the invention relates to weather strips installed on automobile bodies with curves which are swelled toward width direction of the automobiles. Accordingly, the invention does not decrease expanding or contracting state on the hollow seal member 12 sufficiently while the opening seal 10 for automobiles is assembled on the corner part.
Therefore, an object of the present invention is to provide the opening seal for automobiles and method of preparing the same capable of remarkably decreasing the expanding or contracting state on the hollow seal member while the opening seal for automobiles is assembled on the corner part.